高温纳米膜分离及高温高压水循环流通预处理的调控

It is a worldwide big challenge to develop high-efficiency low-cost biomass pretreatment technology. Flowthough pretreatment with high-pressure high-temperature water is getting much attention because of its great performance and no need for additional chemicals. However, "high energy need, high water consumption, and low concentration of liquid hydrolyzate" are the key bottleneck to its application. Targeting at "the three major problems", this project will focus on investigating the regulation of flowthrough pretreatment for high efficiency reduced consumption on energy and water and the concentration of the liquid hydrolyzate and recycling of high-pressure high-temperature water using high-temperature nanoporous membrane. The details of this study are: understanding the behavior of hemicelluloses and lignin during flowthrough pretreatment and the major factors that impact on their degradation, solubilization, and decomposition; developing the regulation to balance the need and provide of heat and water during flowthrough pretreatment;looking and screening for suitable material for the nanommbrane, investigating the relationship of membrane function to nanoporous size and construction; optimizing nanoporous sizes and separation conditions to realize high-rate membrane separation;investigating the stability of nanomembrane,reasons responsible for the stuck of the nanopores, and the technology for quick recovery of membrane function; characterizing the performance of flowthrough pretreatment with separation and recycling of high-pressure high-temperature water using nanoporous membrane. The objective of this study is to build scientific and technology foundation on solving the "the three major problems" of flowthrough pretreatment, with the final goal of developing a new process of high-efficiency low-cost biomass feedstock pretreatment with China's independent intellectual property rights.

高效低成本的原料预处理技术的开发是当今国际的重大难题。高温高压水流通预处理因其优良的效果和无需外加化学品而备受关注，但"能耗高、水耗大、预处理液浓度低"等是制约该技术推广应用的主要瓶颈。本项目针对流通预处理的"三大问题"，将重点研究节能节水高效流通预处理的调控规律和高温纳米膜分离浓缩流通预处理液并回收高温高压水的方法。具体内容包括：揭示半纤维素和木质素在流通预处理过程中的降解、溶解、分解行为及其主要影响因素，建立水热供求平衡耦合流通预处理的调控机制；寻找筛选合适的高温纳米膜材料，研究纳米孔径和结构与膜功能的关系，优化膜分离条件，实现膜的快速分离；研究纳米膜的稳定性能，纳米孔堵塞机理及膜功能快速修复技术；初步评定高温纳米膜分离及高温高压水循环流通预处理的技术性能。为解决流通预处理的"三大问题"并最终建立拥有我国自主知识产权、高效低成本的原料预处理新工艺奠定科学技术基础。

高效低成本的原料预处理技术的开发是当今国际的重大难题。 本研究初步建立了一套研究木质原料流通预处理的方法与实验装置， 测试了不同结构和孔径大小高温纳米膜对高温预处理液分离回收高温水的性能，探索了高温纳米膜快速浓缩流通预处理液的可行性。初步研究表明，纳米孔径为5-10纳米的陶瓷金属复合高温纳米膜对流通预处理液的快速分离浓缩效果良好。该研究的进一步开展，特别是寻找更加合适的纳米膜材料、结构和孔径大小，优化纳米膜的分离操作条件，研究纳米膜功能的修复技术等，可促进该项目研究技术工艺的形成与应用。